Electronic systems and circuits have made a significant contribution towards the advancement of modern society and are utilized in a number of applications to achieve advantageous results. Numerous electronic technologies such as digital computers, calculators, audio devices, video equipment, and telephone systems facilitate increased productivity and cost reduction in analyzing and communicating data, ideas and trends in most areas of business, science, education and entertainment. Typically, electronic systems designed to produce these results consume power. Power consumption can have undesirable impacts and power conservation is often an important design objective. However, traditional attempts at power conservation are usually limited. For example, traditional power conservation attempts do not usually reduce power consumption associated with leakage currents.
A number of electronic systems include semiconductor dies with various components that are utilized to perform a variety of operations. For example, the basic electronic component for performing switching operations in a typical semiconductor die is a transistor. Transistors typically consume energy when switching states and the more times a transistor switches states the more energy it consumes. Modern applications typically include some functions that require a semiconductor die (e.g., processor) to have a relatively large number of transistors and can require the transistor to change states a significant number of times at a relatively fast rate. However, applications also usually include a number of functions that may only involve a relatively few transistors that switch states.
A number of the electronic systems include components that significantly drain the resources and/or reduce the life of a typical limited power source even when not performing switching operations. For example, transistors typically consume some energy due to leakage current even when they are not switching states. While the power consumed by an individual transistor due to leakage current may be relatively small, the aggregate power loss for a large number of transistors can become significant. This power consumption is usually undesirable, especially in systems with limited power supplies.
There are a number of traditional mechanisms that attempt to conserve power in a semiconductor die. For example, some traditional systems attempt to conserver power by clock gating or switching off a clock to a certain number of transistors which stops the transistors from performing switching operations. However, even though the transistor is not switching states in accordance with a clock signal, transistor still typically consumes power due to leakage current. Energy resources for a number of systems are often limited and are expended quickly (e.g., battery power sources in portable devices such as a laptop computer).